Air pump or compressor.



Patented Aug. 8, |899. c. o. soBlNsKI. AIR PUMP 0R COMPRESSOR.

(Application led Apr. 2., 1897.\

2 Sheets-Sheet |l Nn Model.)

N0. 630,525. Patented Aug. 8, |899.

C. SOBINSKI.

AIR PUMP 0R CUMPRESSOR.

(Application filed Apr. 2. 1897.\

2 Sheets-Sheet 2 .No Model.)

. ...un .ilfhmeil UNITEDA STATES vPATENT OFFICE.

CHARLES O.'SOBINSKI', OF ST. LOUIS, MISSOURI.

AIR PUMP vOR COMPRESSOR.

SPECIFICATION forming part of Letters Patent No. 630,525, dated August 8, 1899.

Application led April 2, 1897. Serial No. 630,427. (No model.)

To ctllwtom, it may concern:

Be it known that I, CHARLEs O. SoBINsKI, a citizen of the U-nited States, residing at St. Louis, State of Missouri, have invented certain new and useful Improvements in Air Pumps or Compressors, of which the following is a full, clear, and exact description, referencebeing had to the accompanying drawings, forming a part hereof.

My invention has relation to improvements in air-pumps or compressors; and it consists in the novel arrangement and combination of parts more fully set forth in the specification and pointed out in the claims.

In the drawings, Figure 1 is apart eleva-1 tion of my invention and part section, taken on the line as :cof Fig. 2. Fig. 2 is atop planl view withthe air outlet or escape pipe removed. Fig. 3 is a .plan detail of one of the camplates along which the dogs travel. y Fig. 4. is a detail elevation and middle section, respectively, of the reciprocating pistons. Fig. 5 is a plan view of one of the pistons. Fig. 6 is a detail of the packing and. nap-valves cut therefrom. Fig. 7 is a perspective detail of the plate, corresponding to the cross-head of the ordinary engine, attached to t-he solid piston-rod. Fig. 8 isa perspectiveof the dog mounted thereon. Fig. 9 is a sectional detail on y y of Fig. 1. Fig. 10 is a sectional detail on a z of Fig. 1, with the disk of thedrivingshaftturned a quarter-revolution from the position shown in Fig. l. Fig. l1 is a longitudinal section of the plate carried by the solid piston-rod. Fig. 12l is a similar section of the plate attached to the hollow pistonrod. Fig. 13 is a detail elevationshowing the application of a rock-shaft instead of a revolving drive-shaft. Fig. 14. is a detail plan of the same. Fig. 15 is a detail 'ofthe crankarms carried by the rock-shaft. Figs. 16 and 17 are detail plan views of the plates carried by the piston-rods of said modiiied form of pump.

The object of my invention is to construct an air pump or compressor which for a given stroke of piston will control a maximum volume of air, the present device comprising as an essential feature two pistons operating simultaneously in a single cylinder and suitable inlet and outlet ports disposed on'each side of each piston, whereby the efficiency of `the pump is raised to a point unattained, so far as I am'aware, by any of the existing and prevailing forms of pumps. The present pump is operated from a single rotating or oscillating shaft, the mechanical connections between said shaft and the pistons being such `as to produce a compactness of structure differing essentially from any other device of a similarl nature. Although specifically denominated an air-pump, it will'be apparent that the same may operate on water or other lfluid. In detail it maybe described as follows:

Referring to the drawings, Figs. l and 2, it

Willbe observed Athat I have shown two sets of icylinders, one on either side of a central op- Ierating-shaft, the partsl on one side being 4mere duplicates of the counterpartsn the opposite side, so that a description of one half gof the machine will answer for the corresponding parts of the opposite half. The pump is provided with the Yusual cylinder 1, in which joperate the pistons 2 and 3, the hollow pistonrod 4 of the former loosely receiving the solid piston-rod of the latter, the piston-rods both extending iu the same direction toward the zmain drive-shaft 6, operated by a pulley 7 from any suitable source of power. (Not shown.) Both pistons are reciprocated by 'the rotation of the shaft 6. The latter is I mounted in suitable bearings S,whose lianged fportions 8 are secured to the lateral walls or "plates 9, by which the cylinders 1 1 of the double machine are united. For the sake of ,lightness of construction the plates 9 (which for reasons to appear subsequently are denominated as the cam plates are cut faway, the cut-away portion being covered by a thin plate 10 to4 insure rigidity for the parts. Formed integrally with the flanged portions 8', along the inner surface thereof and about the opening through which the operating-shaft passes, is an offset 11 of peculiar'p'olyg'o'n'al contour, (see Fig. 3,) which passes through a larger opening of similar contour formed in the cam-plate 9, the outer edges of said offset and the inner walls of the opening forming jointlywhen the'parts are assembled suitable cam-slots 12 around the shaft 6 along each wall'or plate 9. ,The hol- ,low piston-rod terminates in an offset 13, with which is formed integrally a plateM, con- ICO neeting together the hollow piston-rods of the double machine, said plate being provided with a longitudinal slot or cut-away portion 15, elongated in the direction of the pistonrod and adapted to embrace the operating or drive shaft G, the plate 11 being located ad jacent to the inner wall of the cam-plate on that side of the machine. The connection between the adjacent ends of the hollow piston-rods is further strengthened by a longitudinallyslotted stiffening bar or plate 1G, located adjacent to the inner surface of the opposite cam-plate l). (See Fig. 10.) Connecting the adjacent ends of the solid piston-rods 5, projecting from the hollow piston-rods within which they operate, is a plate 17, provided with a similarlyelongated opening 13, embracing the drive-shaft, and carried by the drive-shaf t (3 and interposed between the pla-tes 11 and 17 is a disk 20, having located on opposite faces thereof and at points diainetrically removed from cach other antifrietion-rollers 21, whose purpose will be presently described.

Intersecti ng at right angles the slot 15,alon g the inner face of the plate 1t and disposed medially the length of the slot on each side of the same, is .a transverse gnideway or groove 22, and similarly intersecting the slot 1S of the plate 17 is a similar groove 22', the adjacent ends of the grooves terminating in reduced pockets 23 23', cut in the respective plates. Adapted to be guided between the lateral walls of each groove 22 22 is a dog 2%, provided with a longitudinal slot or guideway 25, each dog when insertedinto its groove 22 (or 22) being iiush with the inner surface of the plate by which it is carried. The inner end of that wall of each dog which is directly supported by the base of the groove 22 is provided with a laterally-projeeting lug 2G, which is of such dimensions that when the dogs have been forced apart toward the bases of the grooves, as subsequently to be explained, it (the lug) completelyiills the pocket 23 at the free end of the groove and comes iiush or is continuous with the lateral wall of the slot 15 or 18. (See Fig. 1.) The lng 2G is provided with a pin 27, which is designed to travel in the cam-slot 12 and guide the dog in the path of the slot, as presently to be eX- plained. By way of distinction the dog carried by the plate 17 is lettered 24', its slot 25, and lug 2G', and pin 27, this distinction resulting from the fact that the lug 26/ is deeper than the lug 2G, as the former is extended to pass the thickness of the stiffening-bar 1G to reach the adjacent surface of the cam-plate on that side, the bar 16 having a cut-away portion 2S to accommodate the parts. By reason of the increased depth of the lug 2G the lateral walls of the pocket 23, which receives it, are correspondingly lengthened by providing the plate 17 with an offset or shoulder 29, (see Fig. 7,) in which said pocket is cut, the base of the lng 26' and the offset 2U normally bearing against the inner surface of the cani-plate in the cam-slots of which the pin 27' operates. The rollers 21, carried by the disk 20 of the drive-shaft, freely operate in the slots 25 25 of the dogs, and each dog in its travel along the cam-slot is guided and kept true to its position in its groove 22 or 22 by a rear terminal guide-pin 30 30', passing through a suitable opening 31 or 31, formed in the plates 14c 17 at the bases of the gnideways or grooves 22 22', respectively.

The operation of the device is as follows: It is obvious that as the pistons 2 3 are reciprocated to and from each other the plates 14 17 will be correspondingly reciprocated and the dogs carried by and guided in the grooves 22 22 of said plates will also be reciprocated; but in the reeiprocation of the dogs the latter' are compelled to follow in the path of the cam-slots 12, bringing the adjacent ends of the dogs together at the limit of cach stroke and gradually forcing the dogs apart as they approach the medial or basal portions of the cam-slots. The foregoing merely describes the path taken by the dogs during the reciprocatiou of the pistons; but iu reality it is through the dogs that motion is imparted to the pistons. This is accomplished as follows: Each roller 21 of the disk 2O is adapted to opcrate in the slot 25 25 of the dogs. It may be stated in passing that cach groove 22 22 is of sullieient length to allow the dog to play in the groove a distance equal to the perpendicular distance between a line joining the free opposite ends of the cam-slot and the base or medial portion of said slot, and, furthermore, that the length of each slot 25 25 is such as to allow for the free and uninterrupted passage through it of the rollers 21 during the rotation of the disk 20-that is to say, when the dogs occupy a position along the medial portion of each cam-slot 12 each roller will be approximately at the base of the slot formed in the dog. (See Fig. 1.) Now as rotation is imparted to the shaft G from any source of power it follows that the disk 20 will be rotated. As the disk 2O rotates the rollers 21 thereof, operating as they do within the slots 25 25' of the dogs, will carry the latter with them; but as the dogs cannot describe a circular path (not being pivotally connected to the rollers) they are obliged to travel along the cam-slots 12 to allow of a free and uninterruptedrotationof thcdriving-disk20. The disk with its two diametrically opposite located rollers 21 acts as two crank-arms, each crank-arm during its rotation driving before it one dog of each pair at a time, the other dog of each pair, mounted on the plates 14 17, being carried along bodily by the plate to which it is attached until the pistons have each reached the limit of their respective strokes, when the next dog of each pair will be positively driven by the crank-arms. Fach pair of dogs, it will be remembered, come together at the limit of each stroke of each piston, thus (by their slots 25 25@ as seen by the dotted lines in Fig. 4) forming a continuous guideway for the roller 2]., enabling the lat- IOO IIO

terwithout interruption to freely. pass from the slot of one dog to that of the adjacent dog,

and drive the particular plate carrying the same in the reverse direction. By the construction described -the stroke of either piston corresponds to the full length or distance between the rollers 21, carried by the disk 20, and the device has the advantage of being compact and occupying less room than were ro the piston-rods pivotally connected to the disk 2O and their respective pistons, as is usual where curvilinear motion is converted into rectilinear motion. Under the present construction the circular motion or component of the reciprocating piston-rods is assumed by the dogs. A's seen from Fig. 1, when the crank-arms at Whose free ends the rollers 21 are supposed to be mounted are disposed vertically the pistons 2 3 occupy a normal zo position. When the disk 20, however, has

made a quarter-revolution, the relative positions of the plates 14 17 and dogs carried by` them will be such as to drive each pair of dogs to the limits or adjacent ends ofthe 25 cam-slots 12-that is, the pistons will have reached the limits of their outward'strokes and thus be forced away from each other. (See eXtreme dotted positions in Fig. 1.) When the-disk 20 has made a second quarterrevolution, the parts will again occupy the position shown by solid lines in Fig. 1. At the next or third quarter of a revolution they will be forced'toward their inner limit, (see inner dotted position of the pistons in Fig. 1,)

never passing, however, the inlet and outlet ports with which the cylinder-wall is provided and to which reference will presently be made. At the fourth quarter of a revolution they will again occupy their normal position. The

4o pistons of course reciprocate simultaneously in opposite directions within the same cylinder, being driven by a single drive-shaft 6, the entire length of piston-rod reciprocating along a rectilinear line, the circular component of the motion imparted by the disk 20 being taken up by the dogs, as already described. The piston-rod 4 passes through asuitable stuffing-box at the end of the cylinder.

Disposed along the cylinder-Wall are a se- 5o ries of air-inlet compartments 32, a port 33 leading from each to the cylinder and disposed on each side of each piston in any of its extreme positions, each compartment being controlled by an inwardly-opening Hap-valve 34, weighted by a plate 35, said valve being formed by cutting the flap from a sheet of leather packing 34, covering the several compartments 32, the iiap closing against the inner wall of an air-chamber 36, leading from 6o the common inlet pipe or duct 37. Gorresponding in position to the air-inlet ports 33 are the outlet-ports or discharge-openings 38, controlled by flap-valves 39, constructed similarly to the previous valves and opening into an air-educting pipe 0r chamber 40, leading to a discharge-opening 41. It will be observed that the several pairs of inlet and corresponding outlet openings or ports are disposed in planes parallel to the faces of the reciprocating pistons. ciprocation of the pistons it is apparent that either air will be admitted through the center port 33 between the pistons and simulta- :neously ejected from the extreme dischargeports 38 or air will be admitted through the extreme inlet-ports 33 on top `of each piston and simultaneously discharged through the lmiddle discharge-port 38, thus at all times Ipumping a maximum volume of air.

It is of course apparent that water or any other iiuid could be pumped with the same device.

To insure a tight joint between the pistons and the innerwall of the cylinder, I secure to the outer peripheral rim or ledge 42 of each piston (see Fig. 4) a trough-shaped annular packing-ring 43 on each face of the rim, securing the packing-rings by annular plates 44, connected to the rim by bolts 45.

In Figs. 13 to 17 I have shown a modified form of driving mechanism. The shaft 6' instead of being provided with a disk 2O is provided with two crank-arms 20', each carrying on opposite sides antifi'iction-rollers 21. These rollers operate in the lateral recesses 50, cut in the plates 51 52, attached, respectively, to the solid and hollow piston-rods and corresponding to the plates 17 14 already described, each recess communicating with the longitudinal slot 15' and 18 cut in said plates. To the pin 53 of each roller may be secured a rod or bar 54, whereby the crank-arms 20' can be rocked or oscillated, in this way oscillating the plates 51 52 and the piston-rods of which they form a part, and thereby reciprocating the pistons as if a complete revolution of the crank-arms took place. This modification I illustrate merely to show the possibility of reciprocating the pistons by the mere oscillation of rocking of the crank-arms and shaft G to which they are secured without a complete revolution of such shaft. It is obvious that many other. minor changes could be made without departing from the spirit of my invention.

By disposing the several air-inlet compartments 32 along the peripheral wall of the cylinder and locating the valves 34 in a position to simultaneously communicate with a com- Amon inlet pipe or duct, as described, the present apparatus can be conveniently converted from a compressing-pump to a vacuum-pump, as is obvious.

Having described my invention, what I claim is- 1. An air-pump comprising two sets of cylinders, a central operating shaft disposed transversely to the axes of the cylinders between their contiguous or adjacent ends, two oppositely-reciprocating pistons operating in each cylinder, the piston-rods of the several pistons extending from each cylinder toward the common operating-shaft, and the rod of one piston being hollow to receive the rod of the other piston, air-inlet and air-discharge With each joint re-v IIO openings or ports formed in, or leading from side of each piston, the air-inlet ports on either side of each piston having their corresponding air-discharge ports locatediu like relation to said piston, a series of independent valve-controlled compartments disposed along the peripheral Wall of each cylinder, each compartment communicating with an air-inlet port, and a valve for each discharge opening or port, the latter communicating with a common eduction pipe or chamber, and the parts operating substantially as and for the purpose set forth.

2. In an air pump or compressor,a cylinder, a piston and piston-rod therefor, a d rive-shaft, a suitable dog ingconnection with the piston having a longitudinal slot, a lug projecting from one end of one of the longitudinal surfaces of the dog, a pin carried by the lug, a guide-pin projecting longitudinally the length of the dog and projecting from one end of the same for guiding the dog, cam-slots for the travel of the pin carried by the lug, and intermediate connections between the dog and the drive-shaft for actuating the former and reciprocating the piston upon rotation of the drive-shaft, substantially as set forth.

In testimony whereof I ax my signature in presence of two witnesses.

CIIAS. O. SOBINSKI. \Vi tnesses:

EMIL STAREK, ALFRED A. MA'rHEY. 

